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Biology subjects

Tanabe, H.

Publications and source records attributed to Tanabe, H..

3 recordsLinked to original sources

Immune-induced TCR-like antibodies regulate specific T cell response

Antigen-specific regulation of T cell response is crucial for limiting hyperimmune response. In this study, we discovered that antibodies specific to the antigen peptide-MHC class II complex are produced during helper T cell responses to various antigens. These antibodies specifically inhibited T cell receptor (TCR) recognition of MHC class II molecules presenting specific antigen peptide. We have termed these antibodies immuneinduced TCR-like antibodies (iTabs). Immunization with peptides containing flanking residues induced iTabs, whereas immunization with peptides lacking flanking residues did not. Furthermore, immunization of iTab-inducible peptide as well as iTab treatment suppressed autoimmune disease development. Our findings provide a strategy for suppressing antigen-specific helper T cell responses using specific peptides, potentially controlling autoimmune diseases.

immunology↗

B chromosome and its non-Mendelian inheritance in Atractylodes lancea

Supernumerary B chromosomes contribute to intraspecific karyotypic variation. B chromosomes have been detected in more than 2000 organisms; they possess unique and diverse features, including non-Mendelian inheritance. Here we report one or more B chromosomes in the gynodioecious plant, Atractylodes lancea. Among 54 A. lancea lines, 0-2 B chromosomes were detected in both hermaphroditic and female plants, with the B chromosomes appearing as DAPI-bright regions within the nuclei. Genomic in situ hybridization revealed that the B chromosomes had no conserved A chromosome DNA sequences, which was confirmed by fluorescence in situ hybridization probed with independently dissected B chromosomes. In male meiosis, the B chromosome did not pair with an A chromosome and was therefore eliminated; accordingly, only 20.1% and 18.6% of these univalent B chromosomes remained at the end of meiosis for the 1B lines of KY17-148 and KY17-118, respectively. However, we also found that B chromosomes were transmitted from male parents in 40.8%-44.2% and 47.2% of the next generation; although these transmission rates from male parents were not essentially different from Mendelian inheritance (0.5), the transmission of gametes carrying B chromosomes increased through fertilization or seed development. B chromosomes were transmitted from three of four 1B female parents to 64.3%-92.6% of the next generation, suggesting B chromosome accumulation. We propose that the B chromosome of A. lancea has a specific sequence and persists via non-Mendelian inheritance from female parents. Overall, A. lancea is a useful material for understanding the structure, evolution, and mechanism of non-Mendelian inheritance of B chromosomes.

genetics↗

Analysis of IGHA1 and other salivary proteins post half marathon in female participants

BackgroundHigh intensity exercise, such as in marathons and triathlons, suppresses transient local and systemic immunity. Much is known about the systemic immunosuppression response, but little is known about its local response in the oral cavity, lungs, bronchial tubes, and skin. The oral cavity is an entrance for bacteria or viruses to enter the body. Saliva covers the epidermis of the oral cavity and plays an important role in the local stress response by preventing infection. In this study, we examined the properties of saliva secreted during the local stress response induced by a half marathon (HM) using quantitative proteomic analysis. MethodsThe Exercise group (ExG), 19 healthy female university students participated in (HM) race. The non-exercise group (NExG), 16 healthy female university students had not participated in the ExG. In ExG, saliva samples were collected 1h pre and 2h and 4h post HM. NExG were collected in same time interval. Saliva volume, protein concentration and relative IGHA1 expression were analyzed. In addition, 1h pre and 2h post HM saliva were analyzed by iTRAQ. The identified factors of iTRAQ, analyzed for the ExG and NExG by western blotting. ResultsWe identified kallikrein 1 (KLK1), immunoglobulin kappa chain (IgK) and cystatin S (CST4) as suppression factors, as well as immunoglobulin heavy constant alpha 1 (IGHA1), which has been reported as an immunological stress marker. KLK1 (p = 0.011), IGK (p = 0.002), and CST4 (p = 0.003) were suppressed 2 h post-HM compared to pre-HM, and KLK1 (p = 0.004) and CST4 (p = 0.006) were suppressed 4 h post-HM. There was also a positive correlation between IGHA1, IGK, and CST4 2 and 4 h post-HM. In addition, KLK1 and IGK after 2 h post-HM showed a positive correlation. ConclusionOur study demonstrated that the salivary proteome is regulated and antimicrobial proteins are suppressed post-HM. These results suggest that oral immunity was transiently suppressed post-HM. The positive correlation of each protein at 2 and 4 h post-HM suggests that the suppressed state was similarly regulated up to 4 h after a HM. The proteins identified in this study may have applications as stress markers for recreational runners and individuals who perform high- and moderate-intensity exercises in their daily lives.

physiology↗